Do you Know some freeware for detecting packet sniffing by ISP or others in my DSL copper wire.
I'm using GLASNOST from Max Plank Institute but it gives always the following message
1 out of 3 control flow transfers on port 46202 failed to download any data. It seems like your ISP hinders you from downloading control flow traffic on port 46202 to our test server.
Can someone explain this to me
If sniffing is done right, it is not detectable. Sniffing digitally duplicates your traffic to another device, usually for diagnostic purposes. With several thousands of customers, an ISP will not be sniffing your particular traffic unless the Feds are onto you for kiddie porn, or if you give your ISP some other red flag to watch your connection.
Sniffing aside, the ISP is in control of the traffic flow devices, their switches and routers. These devices are advanced enough to not just block traffic outright, but sometimes limit usage based on criteria/policies. For example, rather than fully blocking BitTorrent traffic, it might greatly hamper it during hours 7 am - 6 pm unless you're paying for Business Class service. Glasnost might evidence this.
Your result indicates port 46202 sometimes does not get thru, where it should work 100% of the time. This may be the ISP's imposed limitation on high TCP ports, but it also may be hardware related. If there's static on your DSL line, it could theoretically lead to dropped packets and such results, but it would be across the board, not just selected ports. One of the Java Speedtest apps would reflect slow speeds if that were the case.
Downloading free software is a legit usage of BitTorrent, so try downloading a large Linux disk image such as Ubuntu. Let your ISP know if it does not approach your subscribed rate, or even fails miserably. But realize by complaining, you could also be jumping onto their radar to have your line "periodically reviewed". But get it fixed if necessary, and download the same ISO image to "test" it afterwards.
This doc explains some Glasnost project details.